Put one tbsp of baking soda in a jar or a bowl and mix with a spoon. Now add 1 tsp of rose water and mix to spread it into baking soda. Wait 2 hours if it's warm or more if it's cold outside...Anyway till it's dry.
Now (be sure the baking soda is DRY!) mix with a spoon, again. Add 1 tbsp of baby powder and mix WELL. And it's done. You can put it under your underarms or even under your feet, like a common deodorant =)